Python as a first language

This presentation makes the case for Python as a first language in undergraduate computer science programs.

Transcript

1. Python as a first language
   Yoav Ram
   June 2018
   

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2. Python is interpreted & dynamic
   Interpreter is great for novice
   programmers
   Dynamic type system allows fast
   prototyping
   

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3. Python is high-level
   Design emphasizes code readability
   “looks like pseudocode”
   

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4. Python design principles
   • Aims for simplicity and generality
   • Semantic whitespaces (newlines, indentation)
   • English keywords (and, or, not, in, is, as)
   • Operator overloading (”hello “ + “world”)
   There should be one—and preferably only one—
   obvious way to do it
   Wikipedia
   

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5. Example: Hello World!
   Java
   public class HelloWorld {
   public static void main(String[] args) {
   System.out.println(“Hello World!”);
   }
   }
   Python
   print(“Hello World!”)
   Complex: classes, accessibility, arrays, functions, static, return
   type (void!), namespaces, standard output… and compilation.
   Simple. Try in online interpreter : tiny.cc/PyHelloWorl
   

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6. Example: simple program
   def f2c(f=None):
   if f is None:
   f = input(“Enter F degrees: “)
   f = float(f)
   return (f – 32) * 5 / 9
   def c2f(c=None):
   if c is None:
   c = input(”Enter C degrees: “)
   c = float(c)
   return 9 / 5 * c + 32
   tiny.cc/PyF2C
   

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7. Python is pluralist
   Cross-platform
   Multiple programming paradigms
   

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8. Programming paradigms
   • Object-oriented programming (C++, Java, C#)
   • Imperative programming (C)
   • Functional programming (Haskell)
   • Event driven & async programming (JavaScript)
   – Co-routines (async) or callbacks (tornado)
   Wikipedia
   

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9. OOP
   class Rectangle(Shape):
   def __init__(self, lower_left, upper_right):
   self.ll = lower_left
   self.ur = upper_right
   def area(self):
   width = self.ur.x – self.ll.x
   height = self.ur.y – self.ll.y
   return width * height
   def __contains__(self, point):
   return (
   self.ll.x < point.x < self.ur.x and
   self.ll.y < point.y < self.ur.y
   )
   

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10. Almost everything is an object
    • strings, lists, dictionaries, tuples, functions,
    classes, types
    • Strong polymorphism
    • Duck typing
    

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11. Functional programming
    generators
    n = len(numbers)
    mean = sum(numbers) / n
    devs = (x – mean for x in numbers)
    squared_devs = (x*x for x in numbers)
    var = sum(squared_devs) / n
    std = var**0.5
    def make_power(a):
    def power(x):
    return x**a
    return power
    square = make_power(2)
    square(4) # => 16
    closure
    

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12. Python is “batteries included”
    Large standard libraries
    Easy to install many 3rd party libraries
    Domain specific distributions
    

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13. Large standard library
    • Files: zip, gzip, json, csv, tempfile, linecache, xml, wave
    • db: sqlite3, dbm
    • Network: socket, ssl, async
    • Web: urllib, http.server, email, ftplib, cgi, html, uu
    • Crypto: hashlib, hmac, secrets
    • Software: logging, unittest, mock, doctest, curses,
    sched, queue, getpass, gettext, tk,pdb, profiler
    • Concurrency: threading, multiprocessing, async,
    futures, subprocess
    • collections, functools, itertools…
    Python docs
    

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14. Many new libraries released every
    month
    During 2015, > 1,500 new packages released every month to PyPI.
    See more stats at PyGarden/stats.
    

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15. Python is free
    Gratis: Free as in Beer
    Libre: Free as in Speech
    GitHub | Mailing lists
    

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16. Python is open
    Open-source software
    Community-based development
    Managed by non-profit Python
    Software Foundation
    

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17. History of Python
    • Developed in 1989-91 by Guido van Rossum in the
    Netherlands
    • Python 2.0 released Oct 2000
    • Many major new features:
    – cycle-detecting garbage collector
    – support for Unicode
    – shift to transparent and community-backed development
    • Python 3.0 released Dec 2008
    – major backwards-incompatible release
    – many of major features backported to Python 2.6 and 2.7
    • Python 3.5 released Sep 2015
    • Python 3.7 beta available, final expected June 2018
    

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18. Python is cool
    Jupyter notebooks, online
    interpreters, code on your phone,
    Raspberry Pi
    

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19. Python is fast enough
    Easy to wrap more C
    Easy to parallelize
    Numerical packages implemented in C
    Cython: transcoder to C
    Numba: JIT compiler
    Benchmark Game | NumFocus Benchmarks
    

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20. Python for data science &
    scientific computing
    With libraries like NumPy, SciPy, Matplotlib,
    IPython/Jupyter,
    Scikit-image, Scikit-learn, and more
    Replacing MATLAB
    Pushed by Google, Microsoft, others
    

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21. Python is popular and has a great
    community
    

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22. Easy to find help on the Internet
    • Python is 6th most popular tag on
    StackOverflow
    stackoverflow.com/tags, May 2018
    

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23. Active community
    • 3rd most active repositories on GitHub after
    Java (incl. Android) and JavaScript (incl.
    node.js)
    • As of May 2018
    • See breakdown at githut
    

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24. Demand for Python
    programmers is high
    

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25. Coding Dojo
    

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26. Python is widely-used
    In academia
    In industry
    In education
    As Wikipedia examples…
    

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27. Python is used at
    Google, Rackspace, Microsoft, Intel, Walt
    Disney, MailChimp, twilio, Bank of America,
    Facebook, Instagram, HP, Linkedin, Elastic,
    Mozilla, YouTube, ILM, Thawte, CERN,
    Yahoo!, NASA, Trac, Civilization IV, reddit,
    LucasFilms, D-Link, Phillips, AstraZeneca,
    Applied Materials, KLA-Tencor, Nova, Lam
    Research, Marvell
    https://us.pycon.org/2016/sponsors/
    https://www.python.org/about/quotes/
    https://en.wikipedia.org/wiki/Python_%28programming_language%29#Use
    https://en.wikipedia.org/wiki/List_of_Python_software
    https://www.python.org/about/success/
    

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28. First language in US CS departments
    1. Carnegie-Mellon: Python, C
    2. MIT: Python
    3. Stanford: Python, Java, JavaScript
    4. Berkeley: Python
    5. U Illinois UC: Python, Java, MATLAB, C
    6. Cornell: Python, MATLAB
    7. U Wash: Python, Java
    8. Princeton: Java
    • Olin: Python
    Phillip Gou @ CACM
    

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29. Phillip Gou @ CACM, 2014
    

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30. First language in Israeli departments
    TAU: Python
    HUJI: Python
    Technion: C
    BGU: Java
    BIU: C
    Haifa: C
    Open U: Java
    2017-2018
    

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31. But why Python?
    Guido was reading some
    Monty Python's Flying
    Circus sketches and thought
    Python would be a cool
    name
    Python 2 FAQ
    

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32. Encyclopædia Britannica Online
    Thanks for listening
    32
    yoav@yoavram.com
    @yoavram
    www.yoavram.com
    

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